Secondary Breakup of Aerated Liquid Jets in Subsonic Crossflow (Postprint)

摘要

An experimental investigation of the secondary breakup of an aerated liquid jet in subsonic crossflow is described. The present test conditions were similar to those encountered in fuel injection in ramjet engines. Previous studies of spray structures of aerated liquid jet in crossflow have been limited to the dilute spray area (downstream distance > 100 jet diameter) using Phase Doppler Particle Analyzer (PDPA) and along the liquid surface using wet- holographic plates. The objective of the present study was to extend these earlier measurements to investigate the dense spray near-injector region immediately downstream of the injector (0-50 jet diameter) where secondary breakup occurs in order to bridge the gap between drop size distribution along the jet surface and those obtained using PDPA in the far-field of the injector. Three-dimensional microscopic digital holography was used to record and measure droplets sizes and locations within the three-dimensional volume of the spray. The test conditions include different gas-to-liquid mass flow rate ratios and jet-to-free stream momentum flux ratios.